When creating a portrait background, the darkest area of background should be

The technique was mural painting and he used either freshly laid or wet lined plaster. he also use water to merge it with the pigment and plaster creating a internal part of the wall

White: titanium white.black: mars black.red: primary magenta, quinacridone red or alizarin crimson, cadmium red light.yellow: primary yellow, diarylide yellow, yellow ochre.blue: primary cyan, ultramarine blue, phthalocyanine blue.orange: pyrrole orange or cadmium orange.green: permanent green.